Feature request: Possibility to use a custom verbose log format?

[linuswillner]

The verbose log function of this library is very handy, as it makes it possible to conveniently log even command runs passed in via template literal. Defining a wrapper function for those is a bit of a faff all said and told.

However, as might be expected, not everyone is using the same log format. That's the case for the project I'm working on, and I'd like the logs to be uniform. Would it be possible to add a way to customize the format used by the verbose parameter? I'd be more than happy with just passing in a function somewhere that can take the command that was just run as a parameter, format it however I need to, and return it to execa to be logged.

[ehmicky]

Hi @linuswillner,

That makes sense.

I would suggest the following. Currently, the verbose option can be 'none', 'short' or 'full'. We could allow it to be a function (line, verboseEvent) => string | undefined instead.

The function maps the line being logged. If undefined is returned, Execa does not log anything. This allows ignoring specific types of messages. This also allows logging to files or remotely instead of the console.

line is the full verbose line string, as formatted by Execa.

verboseEvent is the same information but as an object instead. It has the following fields:

• type {string} among:
  • 'command': when subprocess starts
  • 'output': stdout/stderr output
  • 'ipc': IPC message
  • 'error': error message
  • 'duration': total duration when subprocess ends
• message {string}: serialized and split line-wise (each verboseEvent is a single line)
• timestamp {Date}
• failed {boolean}: same as result.failed
• piped {boolean}: same as result.pipedFrom.length > 0
• escapedCommand {string}: same as result.escapedCommand
• commandId {bigint}: command identifier, incremented from 0
• options {Options}: subprocess options

What are your thoughts on this @sindresorhus?

[sindresorhus]

👍 Sounds quite flexible, which would enable multiple use-cases.

[ehmicky]

Update: I started working on it. :+1:

[ehmicky]

PR at #1130.

[ehmicky]

This was released in 9.3.0. It is documented here and there.